Google Now and its “cards”—those bite-sized alerts, reminders, and personalized recommendations—are so prescient, they’re positively spooky. One such card might tell you that today’s the birthday of a close friend, while another might point out a news article that it somehow knew you’d want to click.

Google Now cards may also alert you to traffic jams on the way home, thunderstorms in tomorrow’s forecast, that dinner rezzie you made for Friday, a thrilling victory by your favorite baseball team, or a hot new bistro in your neck of the woods.

So, what’s going on here? Is Google Now reading our minds or something? Can these Google Now cards be controlled—or stopped?

Read on for 7 things to know about your Google Now cards, starting with...

1. Google Now knows all about you thanks to Google, Gmail and your apps

Google Now gets help from Google itself when it comes to picking out your “Now” cards.

As you may have already guessed, Google Now gets a lot of help from Google itself when it comes to picking out your Now cards—for example, by keeping an eye on what you’ve searched for, which links you’ve clicked, and where you (and your phone and/or tablet) have been.

Google Now has another clever trick up its sleeve: It scans your Gmail, looking for confirmation messages and other clues that might trigger helpful alerts and reminders. (If that sounds creepy, remember that Google already scans your Gmail so it can display “relevant” ads next to your Gmail messages.)

Certain apps on your handset may tip off Google Now about new reminder cards. For example, Spotify might recommend new playlists based on songs you’ve listened to recently, while the Lyft app might let you know how much it’ll cost to take a cab home.

Bonus tip: You can control whether Google uses your so-called “web history” for Google Now cards, search suggestions and other uses.

2. You can change which Google Now cards you get

Just answer a few questions to customize the cards you’re getting from Google Now.

If you’re not loving the cards you’ve been dealt, you can always nudge Google Now in a different direction.

For example, you can tell Google Now that you want your weather cards with degrees in Celsius rather than Fahrenheit, or that no, you don’t want to see any more cards about that new café down the block. You can even nix an entire category of cards—such as, say, cards about recent stories that might interest you.

Just tap the (tiny) three-dot menu button sitting on the top-right corner of a card (or the little “i” button if you’re using Google Now for iOS), and answer the questions that follow (like “Which distance units do you prefer?” and “Continue to get updates for your research projects?”). Google Now will remember your likes and dislikes and deal new cards accordingly.

3. You can dismiss a card with a swipe

Done reading a Google Now card? Just dismiss it with a swipe.

Once you're done with a specific Google Now card, just swipe it off the screen, a gesture that essentially marks a card as “read” and clears the clutter from your Google Now screen.

4. You can tell Google Now about your interests

You can tell Google Now a little more about yourself in the “Customize” menu.

Say you’re an otherwise proud San Franciscan who (when it comes to football, anyway) is bleeding green. There’s an easy way to tell Google Now that your favorite NFL team is, in fact, the Philadelphia Eagles, and not the Niners.

For Android devices:

Tap the three-line menu button in the top-left corner of the main Google Now screen, tap Customize > Sports, then Add a team.

While you’re at it, you can also add stock tickers, specify your home and work addresses (handy for helping Google Now serve up cards about your commute), your cable company, and your favorite streaming-video services.

A final category labeled “Everything else” lists a hodge-podge of details that’ll help tailor your other Google Now cards, including questions you may have answered after tapping the three-dot menu button for a specific card.

For iOS:

The iOS version of Google Now offers many more options for customizing your Now cards. Tap the three-dot button in the top-right corner of the screen, tap Settings, then scroll down to the Cards section. From there, you can tweak the settings for more than a dozen categories, from birthdays and flights to travel and weather.

5. You can tee up a Google Now reminder card

Reminders are among the few Google Now cards that you can set up yourself.

Typically, Google Now doles out your daily cards automatically, with a bare minimum of effort on your part. One notable exception, though, is reminders.

Tap the three-line menu button in the top-left corner of the main Google Now interface (or, if you’re on iOS, tap the three-dot button in the top-right corner of the screen), tap Reminder, then create a reminder for yourself.

Once you do, Google Now will deal a reminder card when the time is right, or when you’re approaching a specific place (if you set a “geofence” in your reminder rather than a time).

Bonus tip: Rather than going to the trouble of tapping out a reminder, just tap the microphone in the Google search box and tell Google Now to remind you of something.

6. Google Now reminders can set off Android or iOS notifications (or not, if you'd prefer)

You can disable Google Now notifications in just a few taps.

Whether you’ve got a dinner reservation coming up, a sunny day in your future, or (gulp) a flash flood headed your way, you might see Google Now card alerts popping up in your Android or iOS notification window.

If you don’t want Now cards cluttering your notifications, there’s an easy fix.

For Android:

Tap the three-line menu button at the top of the Google Now interface, tap Settings > Now Cards, then flip off the Show notifications for card updates switch.

For iOS:

Tap the three-dot menu button in the top-right corner of the screen, tap Settings, then toggle the Notifications setting.

7. You can turn off Google Now cards altogether

Had enough Google Now cards? You can always just turn them off.

If all these Now cards are more annoying than they are helpful, you can ask Google Now to deal you out.

For Android:

Tap the three-line menu button again, tap Settings > Now cards, then switch off the Show Cards setting. In the confirmation pop-up, tap Turn Off to deactivate Now cards on the device you’re using, or check the box to wipe all your Google Now preferences and stop dealing cards on all your Google handsets.

For iOS:

Tap the three-dot menu button in the top-right corner of the screen, tap Settings, then flip off the Now switch.

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